Volcker's originally proposed rule - as part of the 2010 Dodd-Frank Wall Reform Act - was intended to restrict U.S. banks or an institution that owns a bank from executing riskier trading strategies for the firm's personal account while putting their customers money at risk. Critics of such "proprietary trading" say the typical strategies and volatile returns often resembled the speculative nature of a hedge fund than a bank. (Learn more here.)

"Banks have stopped their straightforward proprietary trading operation, and they've largely cut back on their hedge funds and equity funds," Volcker said in the interview broadcast Thursday. "And as the managements and the directors finally understand that 'yes, this is a law that has to be followed,' they'll be able to manage their trading desks in what I think is an effective way."

Volcker said he isn't frustrated by the lack of progress but admits he doesn't know why the rule hasn't been fully adopted yet.

"Whether the [final] regulation has to be as complicated, I don't know what the new regulation will be," said Volcker. "But I don't think it needs to be as complicated as our initial regulation, which got a big reaction."

In prepared remarks at a recent banking conference, Treasury Undersecretary Mary Miller said, "Our goal is to achieve a strong and consistent [Volcker] rule, although the process is not as easy or simple as any of us would like."

CNBC

CNBC is the recognized world leader in business news, providing real-time financial market coverage and business information to nearly 800 million homes worldwide, with headquarters on 3 continents and 20 bureaus around the globe. Award-winning journalists provide content on TV as well as online - where cnbc.com is the #1 non-portal business and news website. Our goal is for our consumers to Capitalize on CNBC - to increase their knowledge and profit from it. We want to make them the smartest people in the room; keep them ahead of the curve; make them members of an elite club.
CNBC. First in Business Worldwide.